Here's an interesting LAT article on the hukou system still prominent in China that is meant to keep populations under geographic and political control but especially serves to keep marginalized those who choose to buck the system and seek work outside their literal station.
North Korea has a similar system, though its enforcement is much stricter.
From the LAT:
BEIJING — For millions of Chinese, the difference between a life of struggle and one of opportunity comes down to a little red booklet known as the hukou .
To read the full article, click on this link or copy and paste it into your browser: http://www.latimes.com/la-fi-china-hukou-20121212,0,3483388.story
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